Cisco BPX 8600 Series, Руководство по установке и настройке

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 21 Configuring ATM Connections
Traffic Policing Examples
Figure 21-20 CBR Connection, UPC Overview
Figure 21-21 shows a CBR.1 connection policing example, with policing set to 4, where the CDVT
depth of the single leaky bucket is not exceeded, and all cells, CLP(0) and CLP(1) are admitted to the
network.
For CBR connections, Leaky Bkt 1
ensures that the combined CLP=0
and CLP=1 cell traffic stays in PCR
compliance within the CDVT limits.
Leaky Bkt 1 admits compliant CLP
cells to the network, and discards
non-compliant CLP cells.
CBR Traffic
CPE
Multiple PVCs
To UPC for each
individual PVC
Time
Cells
per
sec.
PCR
Clumping
(Cells arriving early, i.e, at a
higher than contracted rate)
Cells arriving late
(at a less than
contracted
cell rate)
Note: The notation 0, 1, and 0+1 refers to the types of cell being specified:
cells with CLP set to 0, CLP set to 1,or both types of cells, repectively.
For example, CLP(0), CLP(1), and CLP(0+1).
TAT TAT TAT TAT TAT TAT TAT TAT
Verify
VPIs,
VCIs
(TAT=Theoretical Arrival Time for cells per traffic contract)
Discards incoming CLP(0+1) cells if Bkt
1 depth > CDVT(0+1). Does not tag cells.
If Bkt 1 depth < CDVT(0+1), passes CLP=0
and CLP=1 cells on to network.
Policing
Policing: 4 = PCR Policing only
5 = off
CLP=1
5
CLP=0
4
CLP=1
3
CLP=0
2
CLP=0
1
+
PCR(0+1)
CDVT(0+1)
Time interval variations
Leaky Bkt 1
Admit to network
CLP=1
5
CLP=0
4
CLP=1
3
CLP=0
2
CLP=0
1
Example: Policing = 4